Pig liver phosphomevalonate kinase (EC 2.7.4.2) has been purified to homogeneity as shown by polyacrylamide gel electrophoresis. The molecular weight estimates range from 21,000 to 22,500. Each molecule is composed of one polypeptide chain. The presence of SH-containing reagents is essential for the preservation of enzymes activity at all steps in the purification. The enzyme shows absolute specificity for ATP and requires for activity a divalent metal cation, Mg2+ being most effective. The optimum pH for the enzyme ranges from 7.5 to over 9.5. Kinetics are hyperbolic for both substrates, showing a sequential mechanism; true Km values of 0.075 mM and 0.46 mM have been obtained for phosphomevalonate and ATP, respectively. Amino acid composition shows a high content of acid amino acids, one cysteine residue per molecule of enzyme, and the absence of methionine. The results obtained suggest that the enzyme plays no regulatory function in cholesterol biosynthesis in pig liver, although a variable enzyme content was detected in different livers.
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http://dx.doi.org/10.1021/bi00552a003 | DOI Listing |
J Cardiothorac Surg
January 2025
The First Department of Cardiology, Beidahuang Industry Group General Hospital, Harbin, 150000, Heilongjiang Province, China.
Objective: it was to evaluate the efficacy and safety of rapamycin-eluting stents at different doses in the treatment of coronary artery narrowing in miniature pigs.
Methods: a total of 20 miniature pigs were randomly assigned into four groups: S1 group (low-dose rapamycin-coated stent, 55 µg/mm), S2 group (medium-dose rapamycin-coated stent, 120 µg/mm), S3 group (high-dose rapamycin-coated stent, 415 µg/mm), and D0 group (bare metal stent). The stent size was 3.
J Vasc Interv Radiol
January 2025
Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS 66506, USA; Department of Biomedical Engineering, The George Washington University, Washington, DC 20052, USA. Electronic address:
Purpose: To determine the technical feasibility of discriminating discontiguous from contiguous ablation zones between a pair of microwave ablation (MWA) applicators using broadband microwave transmission signal measurements in an in vivo porcine liver model.
Methods: Dual applicator 2.45GHz MWA was performed using one directional and one omnidirectional applicator, spaced 3cm apart, under imaging guidance.
Int J Hyperthermia
December 2025
Department of Radiology, University of Wisconsin, Madison, WI, USA.
Purpose: The application of histotripsy, an emerging noninvasive, non-ionizing, and non-thermal tumor treatment, is currently limited by the inherent limitations of diagnostic ultrasound as the sole targeting modality. This study evaluates the feasibility and accuracy of cone beam computed tomography (CBCT) guidance for histotripsy treatments in an porcine model.
Materials And Methods: Histotripsy treatments were performed in the liver of seven healthy swine under the guidance of a C-arm CBCT system that was calibrated to the robotic arm of the histotripsy system.
Biol Reprod
January 2025
Department of Animal Science, Texas A&M University, College Station, TX, USA.
The creatine (Cr) biosynthesis pathway buffers ATP in metabolically active tissues. We investigated whether sex of fetus and day of gestation influence Cr in endometrial and conceptus tissues from gilts on Days 60 and Day 90 (n = 6 gilts/day) of gestation. Uterine and conceptus tissues associated with one male and one female fetus from each gilt were analyzed for creatine, mRNAs, and proteins for Cr biosynthesis.
View Article and Find Full Text PDFAnim Nutr
December 2024
Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
[This corrects the article DOI: 10.1016/j.aninu.
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